Steve Gray wrote:
> I thought I saw somewhere that one could read out coordinates from a
> Graphics plot, according to the mouse position. I can't find it now,
> and I don't see how it would work with Graphics3D. But anything would
> help. Thanks for any info.
If you search MathGroup for "3D locator", you will find several threads
on this topic. Here's one:
http://groups.google.com/group/comp.soft-sys.math.mathematica/browse_thread/thread/3f40635cfe3356d6/dd11ad46016b8475
The idea is to use MousePosition["Graphics3DBoxIntercepts"] to find out
where a line perpendicular to the screen intersects the 3D bounding box.
If you are only interested in 2D, take a look at Locator, or, in
Mathematica 6.0.2, the "get coordinates" drawing tool accessible from
Graphics -> Drawing tools (CTRL-D).